Newbee, You have an alligator snapping turtle which is a heckuva predator and not at all like the run of the mill turtles you usually see sunning on a log. One is an opportunist and the other a hunter. Depending on size, he may be ancient and worth keeping around for sentimental reasons. It sounds like a whopper. On the other hand, if you intend to be the only predator on the pond, I'd eliminate it. I'm not much of an environmentalist but I'd try to live trap it and relocate it. Size of the pond might make a difference. I like turtles a lot more than ducks.
